This invention relates to dental restorative bridgework, more particularily to a modular system for restorative dentistry which makes possible the provision of permanently installed replacement teeth which can be shaped to an individual patient's needs by modification of pre-fabricated parts at a relatively low cost and in a relatively short time, in contrast to fixed bridgework that is made entirely in an outside laboratory from impressions taken on the patient.
Prior attempts to provide a series of component parts to be assembled into a dental bridge from a commercial package of parts have yielded only fixed bars or beams on which removable pontics are carried. These pontic devices use clamps, springs, and the like, which are subject to wear and breakage due in part to undesirable stress concentrations, and do not provide the accuracy of fit that can be provided by permanently fixed artificial teeth. They generally lack complete lower portions, and so are cosmetically unsightly, and tend to be unsanitary and therefore not bio-compatible.
The fabrication of fixed bridgework entirely in an outside laboratory from impressions taken on the patient is expensive and time consuming. In the present state of the art, a dentist has a choice between ceramo-metal bridgework, and bridgework made out of cast gold (or other precious or semi-precious metal) with acrylic facings. Both techniques are technologically complex and require people with special skills. In practice it is found to be unrealistic to expect that a dental technician, who in the vast majority of cases is located at a considerable distance from the dentist and patient will be able to produce the bridgework with the required accuracy of fit and occlusion and the desired cosmetic appearance. It is not unusual for a dentist in search of a competent laboratory to send work to one located hundreds or thousands of miles away. Even then, critical occlusal adjustments are most often required after the finished bridgework has been permanently installed in the patient's mouth. Not unexpectedly, the cost of this form of restorative dentistry has escalated dramatically.
The present invention has as principal objects to minimize the use of outside skills and to give the dentist replacement tooth modules or elements (pontics) which will enable the dentist to provide fixed bridges from prefabricated component parts which will fit as accurately as and are cosmetically equal or superior to custom-made permanent bridgework and which can be made in shorter time and at less cost than custom-made permanent bridgework. The invention contemplates the provision of a wide variety of component parts, including pontics in a wide variety of sizes, shapes, and shades, which can be ordered by the dentist for early delivery from a central depot, to replenish the dentist's own stock as needed. The invention further contemplates unique methods and means to make occlusal adjustments, and to fabricate complete pontics in the patient's mouth, to the end that high quality restorative dentistry will be available at greatly reduced cost to a larger number of consumers.